Not so sure...in the Promise Keepers, they were limited to the Mall. They had no one on the Capitol grounds. That gives me a figure in the 700k range for the Mall itself.
That means capacity on the Mall is at least double the ticketed areas on the chart.
(I hope I interpreted your question correctly.)
Yes, the mall also includes the public area shown on the chart. The public area was being used for other events on Saturday. The rally consumed much of the ticketed area - which can hold 240k according to the chart - but the portion of the ticketed area represented by the rectangular field remained largely unpopulated.
The rectangular field appears to be about 1/4 of the ticketed area, so it would seem fair to say that about 180k rally members were on the mall. I recognize that the event was dynamic - people were walking along Pennsylvania Avenue and coming and going all day - so the actual number of participants will be higher than the number on the mall at any given time. How much higher is anybody's guess, but I would think anyone who says the crowd was a couple of hundred thousand is not too far off.